The blog says that HNK (the purported antidepressant) is a known metabolite of ketamine, but then claims: > However, getting regulatory approval for such a stu

The blog says that HNK (the purported antidepressant) is a known metabolite of ketamine, but then claims: > However, getting regulatory approval for such a study, which would technically (as far as I know) be a first-in-man trial of HNK, might take a long time. I don't understand this. We already know that when we give ketamine to patients they are exposed to HNK. Is there a real risk that it is more dangerous in isolation? Even if caution is required in the first patients, why do we accept as normal that developing treatments like this should involve years of waiting for bureaucratic approval?